OTTERVILLE, Ont. - A Mother's Day tragedy that left a nine-year-old girl dead has devastated this tight-knit community south of Woodstock, Ont., after an already brutal weekend on area roads.

Police didn't release the identity of the girl, who was one of five people -- three of them kids -- killed in Southwestern Ontario crashes on the weekend.

"We finally have nice weather, we've had a long, long winter and there are a lot of pedestrians out there, and motorcycles and farm vehicles," said OPP Const. Lisa Narancsik said. "We have to practice our safe driving."

Other crash victims included a 13-year-old Windsor, Ont., girl who was a passenger in a car that was struck by a tractor-trailer on Hwy. 401 Saturday, and a 16-year-old Sarnia, Ont., boy who was on his skateboard when he was killed in a hit-and-run.

The nine-year-old girl who was killed was on her way to church when the woman driving the car she was in made a left turn and collided with a fertilizer sprayer truck. Three other children in the vehicle were treated for minor injuries.

The crash happened "around the corner" from the scene of an accident that killed motorcyclist David Howard, 48, of Woodstock, in the hamlet of Springford, Ont., a day earlier, Narancsik said. His bike went onto the shoulder of the road and into a ditch Saturday.

"Most people who live in Otterville know each other and you can imagine... It's going to be a devastation for the whole community," she said.

Also Saturday, Marc Lafontaine, 35, and his passenger, Alyssa Smulders, 13, both of Windsor, died on Hwy. 401 near Chatham, Ont., after a tractor-trailer travelling in the opposite direction crossed the median and hit their car.

The weekend of carnage began Friday night, when Devin Hughes, 16, of Sarnia, Ont., was struck in a hit-and-run crash by an SUV while on his skateboard, running an errand for his girlfriend. A 22-year-old Sarnia man turned himself in to police Sunday morning and is charged with criminal negligence causing death and failure to remain at the scene.

Hughes' death triggered an outpouring of support on social media from friends and acquaintances who described him as "full of life."

"He was a handful - he had ADHD and behavioural issues that made him tough to work with at times - but I tell you that kid had a heart of gold," his stepmom Shelly Wilde said.

Meanwhile, in Otterville, neighbours were left with the memory of a horrific day they'll likely never forget.

"I felt so helpless," said Kathy Gould, who was one of the first to arrive at the scene and tried to comfort the other children. "I said, 'It's OK, it's OK. Help is on the way', " Gould said. "I felt so helpless."